NCTM Position Statement
http://www.nctm.org/about/content.aspx?id=12590

NAEYC Position Statement
Early Childhood Mathematics: Promoting Good Beginnings
http://www.naeyc.org/files/naeyc/file/positions/psmath.pdf

Mathematical activities for parents and their 2- to 5-year-old children
http://www2.ed.gov/pubs/EarlyMath/index.html

Resources for Early Childhood: Mathematics
http://rec.ohiorc.org/mathematics.aspx

NCTM Illuminations: Resources for Teaching Math
http://illuminations.nctm.org/

AAAS Project 2061: Dialogue on Early Childhood Mathematics
http://www.project2061.org/publications/earlychild/online/experience/smith.htm